再加100分,求解

[阿达King哥]

http://community.csdn.net/Expert/topic/5547/5547176.xml?temp=.6938593

[最后一只恐龙]

web上画图不是这么画的，下面文章2.2部分，我blog上的：
http://blog.csdn.net/Ivy_zheng/archive/2007/03/23/1538170.aspx

[阿达King哥]

楼上，你的做法的原理跟我的有区别吗?

[emenwin]

学习

[yixianggao]

俺读的是 pub_info 的 logo 图像，应该没区别，从下往上依次调用代码如下：


数据访问层

/// <summary>
/// 根据 出版社 Id 选择 Logo 图像。
/// </summary>
/// <param name="pubId">出版社 Id。</param>
/// <returns>Logo 图像字节数组。</returns>
public static byte[] SelectLogoByPubId(string pubId)
{
string sqlText = @"
SELECT
logo
FROM
pub_info
WHERE
pub_id = @pub_id
";
SqlParameter[] commandParameters = new SqlParameter[1];
commandParameters[0] = new SqlParameter("@pub_id", pubId);

return (byte[])SqlHelper.ExecuteScalar(WebConfigReader.LocalPubs, sqlText, commandParameters);
}


ImageReader.aspx.cs

public partial class ImageReader : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
string pubId = Request.QueryString["pubId"];
Response.ContentType = "image/jpeg";
byte[] byteImage = PublishiersProcessor.GetLogoByPubId(pubId);
Response.OutputStream.Write(byteImage, 0, byteImage.Length);
Response.End();
}
}

BookInfoListByPublisher.aspx.cs

// 读取出版社 Logo
this.imgPublisherLogo.Visible = true;
this.imgPublisherLogo.ImageUrl = string.Format("~/ImageReader.aspx?pubId={0}", PubId);

[yixianggao]

忘了说了，pub_info 是 pubs 库的，但字段类型一致！

[yixianggao]

找到了，Employee 的 photo 里保存的是 gif 格式，因此 有 78 的偏移量！

Pub 库就没这事儿！

// 78 is the size of the OLE header
// for Northwind images.
// There's no header in PUBS as PUBS
// just contains the raw image bits.
int offset = 78;

详见！
http://www.ftponline.com/vsm/2002_07/online/hottips/esposito/


俺试了试，可以看到！

ImageReader.aspx.cs

// 改成雇员 Id 就可以了
string pubId = Request.QueryString["pubId"];
byte[] byteImage = PublishiersProcessor.GetLogoByPubId(pubId);

MemoryStream ms = new MemoryStream();
// 78 is the size of the OLE header
// for Northwind images.
// There's no header in PUBS as PUBS
// just contains the raw image bits.
int offset = 78;
ms.Write(byteImage, offset, byteImage.Length - offset);

Bitmap bmp = new Bitmap(ms);

Response.ContentType = "image/gif";

bmp.Save(Response.OutputStream, ImageFormat.Gif);
ms.Close();